<?php
$stringInDb = "DJâ€™en en turntablism";
$stringInDb = "hoe ben je hier dan gekomen, hÃ¨?";
//echo utf8_decode($stringInDb);
//echo utf8_encode($stringInDb);
//echo mb_convert_encoding($stringInDb, 'UTF-8', 'ISO-8859-1');

$translation = array(
    'â€™' => "'",
    "â€\"" => '-',
    'Ã©' => 'é',
    'Ã¨' => 'è',
    'Ã¨' => 'è',
    'â€œ' => '"',
    'â€' => '"',
    'â€˜' => "'",
    'Ã¢' => 'ã',
    'Ã"' => 'ä',
    'â€"' => '–',
    'â€“' => '–',
    'Ä«' => 'ī',
    'é˜´' => '阴',
    'é™°' => '陰',
    "é˜³" => "阳",
    "é™½" => "陽",
    'Â´' => "'",
    'Ã¼' => 'ü',
    "Ã,Ã'" => "'",
    'â€¢' => '–'
);


foreach( $translation as $find => $replace ){
    $stringInDb = str_replace($find, $replace, $stringInDb );    
    //$output = preg_replace("/" . $find . "/", $replace, $input );
};

echo $stringInDb;